Sound-reproducing device



Jan. 28 193m.

E. S. PRIDHAM ET AL SOUND REPRODUCING DEVICE med June 14. 1922 -2Sheets-Sheet l In enters Edwin SJrid/uzm Peter L. Jbnsen y fliiornegrsJan. 28,- 1930 E. s. PRIDHAM ET AL scum) REPRODUCING DEVICE Filed June14 1922 2" Sheets-Sheet 2 Elnreziors Ed win .SZPr

fliior l a l I I l I I l I l l I I l I Ieter .J 9 L ens n la egrsPatented Jan. 28, 1930 UNITED STATES PATENT OFFICE EDWIN S. PBIISHAM ANDPETER L. JENSEN, OF OAKLAND, CALIFORNIA, ASSIGNORS TO THE MAGNAVOX 00.,OF OAKLAND, CALIFORNIA, A CORPORATION OF ARIZONA SOUND-REPRODUCINGDEVICE Application filed June 14,

This invention relates to sound reproducing devices, and has for itsobject to combine 1n a single instrument a phonograph and an electricalsound reproducer with means for optionally placing one or the other intocommunication with a horn whereby sound waves may be reproduced eitherelectrically or acoustically.

The device includes an electrical sound amplifier which is so arrangedthat it may be used in connection with the phonograph and at other timescan be hooked up with a radioreceiving set to reproduce the sounds ingreatly amplified tone. 1 y

One form which our invention may assume is exemplified in the followingdescription and illustrated in the accompanying drawings, in which- Fig.1 shows a diagram of anapparatu embodying our invention.

Fig. 2 shows a front view of a phonograph cabinet within which themechanism is arranged. y

In its present form, the device comprises a horn 10, which is preferablyarranged within a cabinet 11. This horn has a branch conduit 12extending to a swinging tone arm 13 which carries a phonographreproducer 14. Anotherbranch conduit 15 extends to an electro-dynamictelephone receiver 16. Preferably, this receiver is of the type shownand described in our rior application, Serial No. 377,354, being nowncommercially as a Magnavox. Between the branch conduits 12 and 15 is avalve .17, pivoted at 18 and adapted to be moved to permit one branch tobe put into communication with the horn, while shuttin oil the otherbranch. The electro-dynamid receiver is adapted to be hooked up to aradio-receiving set, as shown at K in dotted lines in Fig. 2.

The phonogra h reproducer 14 is shown as co-operating .wit a soundrecord 19 carried on a turn-table 20 for ordinary phonographic playing.In addition to the reproducer 14 we show a combined phonographreproducer and transmitter 21 carried by a swinging support 22 andhaving electrical connections with the electro-dynamic receiver 16 suchthat the sounds from the phonograph record 1922. Serial No. 568,309.

may be transmitted through the electro-dynamic receiver and sent outthrough the I by wires 24 and 25 with a movable coil 26 on theelectro-dynamic receiver. This coil is fixed to the diaphragm 27 of thereceiver. Points 0 and D are connected by wires 28 and '29 with anelectro-magnet 30 of the said receiver. Terminals E and F are connectedby wires 31 and 32 with the radio-receiving set K, and terminals G and Hare connected by wires 33 and 34 with the battery of the radioreceivingset. When the switch is thrown to engage the terminals E, F, G and H thetelephone currents from the radio-receiving set pass through theelectro-dynamic receiver where they are amplified and sent out throughthe branch conduit 15 and horn 10.

Terminals K and L are connected by wires 35 and 36 with the combinedreproducer andtransmitter 21. In the last-named circuit we show abattery 37 and a rheost-at 38. The other terminals I and J are connectedby wires 39 and 40 with the wires 35 and 36 and include a condenser 41.When the switch is thrown to contact with the terminals I, J, K and L;the sounds from the combined reproducer and transmitter are transmittedtelephonically to the electro-dynamic receiver 16 and sent out inamplified tone through the branch conduit 15 and horn 10.

In addition to the electrical reproduction and amplification of thephono raphic sounds, the phonograph may be playe in the ordinary waythrough the reproducer 14 and branch conduit 12.

Preferably the entire mechanism above described is housed in a singlecabinet which is also designed to contain the radio-receiving set andits batteries.

Various changes in the construction and arrangement of the several partsherein shown and described may be employed without departing from thespirit of our invention as disclosed in the appended claims.

Having thus described our invention, what we claim and desire to secureby Letters Patcut is;

1. In a sound reproducing device, the combination with a sound record, acombined phonographic reproducer and transmitter cooperating with thesound record, an electrically operated telephone receiver, a radioreceiver set, electrical connections between the telephone receiver andthe transmitter aforesaid, electrical connections between the telephonereceiver and the radio-receiving set, and a switch for controlling saidconnections whereby to connect the receiver with the phonograph or withthe radio-receiving set at the option of the operator.

2. In a sound reproducing device, the combination with a sound record aphonographic reproducer co-operating therewith, a combined soundreproducer and transmitter also co-operating with said record, anelectro-dynamic receiver, a horn having a branch conduit connected tothe first-mentioned sound reproducer and a second branch conduit connected with the electro-dynamic receiver,

' means to place either branch conduit into communication with the hornwhile closing the other and electrical connections between the combinedreproducer and transmitter and the electro-dynamic receiver whereby thesound waves from the. phonograph may be transmitted through theelectro-dynamic receiver for electrical reproduction or through thefirst-mentioned reproducer for acoustical reproduction.

3. In a sound reproducing device, the combination with a sound record, aphonographic reproducer co-operating therewith, a combined soundreproducer and transmitter also co-operating with said record, anelectro-dynamic receiver, a horn having a branch conduit connected tothe first-mentioned sound reproducer and a second branch conduit conorwith the radio-receiving set at the option of the operator.

4. In a sound reproducing device, the com-

